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From: Fernando Cacciola (fcacciola_at_[hidden])
Date: 20011025 17:48:41
 Original Message 
From: Noah Stein <noah_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Thursday, October 25, 2001 7:29 PM
Subject: RE: [boost] Math constants for naive and gurus?  which constants
do you want?
> Original Message
> From: Ed Brey [mailto:edbrey_at_[hidden]]
> Sent: Thursday, October 25, 2001 1:45 PM
> To: boost_at_[hidden]
> Subject: Re: [boost] Math constants for naive and gurus?  which
> constants do you want?
>
> > in boost::math would be fine. Of course, I find the concept of
> > representing an irrational number using a rational class kind of
> > amusing, but I suppose it might have practical value.
>
> Maybe there should be an irrational number class? I should think it would
> only take minutes for somebody to come up with an exact representation of
pi
> or e in such a class. :)
>
Both rational and irrational numbers (real numbers) are typically
approximated with floating point types.
And typically, there is a class named something like big_float or real to
support extended or arbitrary precision real number approximations.
We have a bigint, a rational, even an interval (it's in the files section);
so what we need is a big_float<> class. Anyone?
Seriously, I think we might really need a big_float<> class before users
start to believe that rational<bigint> can be used as a replacement for long
double for higher precision needs; this isn't the correct usage of a
rational class.
BTW, there isn't any *exact* representation of pi,e, etc.. because they
don't have an *exact* value :)
Fernando Cacciola
Sierra s.r.l.
fcacciola_at_[hidden]
www.gosierra.com
>
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